Imidazolinone compounds useful as herbicidal agents are described in U.S. Pat. Nos. 4,188,487; 4,297,128; 4,554,013 and 4,798,619. The imidazolinones are best exemplified by the commercial products imazaquin, imazethapyr, imazamethabenz and imazapyr.
Though imidazolinone compounds gradually degrade in the environment, residues remaining in the soil should be monitored so as to provide the most efficacious weed control while avoiding possible damage to follow crop plants. Current techniques used in determination of imidazolinone compound concentrations in soil, water or plant samples are gas chromatography and high-performance liquid chromatography. However, the high cost of equipment, materials and labor required to perform the tests makes their routine use cost prohibitive. Alternative simple and rapid methods for determining the presence and concentration of imidazolinone compounds in soil, water or plant samples are desired.
Enzyme-linked immunosorbent assay (ELISA) technology has been applied in residue analyses of agrochemicals. W. Newsome, Pesticide Science and Biotechnology (Oxford: Blackwell Scientific Publications, 1987), pp. 349-352, describes the use of an ELISA system for the determination of iprodione in plant samples. ELISA is specific, easy to perform and lends itself to automation and scale-up.
J. C. Hall, et al., Weed Technology, 4, pages 226-234, 1990 describes the advantages of ELISA technology and the development and use of ELISA procedures for trace analysis of 2,4-D and picloram.
The application of ELISA technology requires the use of an antibody specific for the compound of interest. Current ELISA technology utilizes antibodies which are not suitable for the determination of the presence and concentration of imidazolinones. If antibodies against imidazolinone compounds could be prepared, then application of ELISA technology might allow for simple and rapid testing of soil, water or plant samples for imidazolinones.
It is an object of the present invention to provide a simple, efficient and cost effective method for determining the presence and concentration of imidazolinone compounds in soil, water or plant samples.